Futuro: raíces irregulares

In the simple future, twelve high-frequency verbs refuse to use their full infinitive as the stem. Instead of tener-é, you say tendré. Instead of poner-é, you say pondré. The endings stay completely regular — the same -é, -ás, -á, -emos, -éis, -án you already know — but the stem is shortened, modified, or replaced. Once you have learned these twelve, you have learned every irregular form of the future tense. There are no other surprises.

Better still, the same twelve stems power the conditional (tendría, pondría, diría). Learn this list once, and you have unlocked roughly half the irregular forms of two tenses simultaneously. This page groups the twelve by pattern, gives all six forms for each, and shows how the same logic carries over to the conditional and to the future perfect.

The twelve irregular stems, grouped by pattern

The irregular stems fall into three groups, each with its own logic.

Twelve verbs, three patterns. Notice that the endings are still regular in every case: you attach -é, -ás, -á, -emos, -éis, -án exactly as you would for hablar, comer, vivir.

Group 1: the -d- verbs (tener, poner, salir, venir, valer)

These five verbs replace the infinitive's last vowel with a -d-. They are all -er or -ir verbs whose stems end in -n- or -l-, and the -d- is inserted to ease pronunciation between the consonant and the -r of the ending.

A useful detail: any compound of these verbs follows the same pattern. Mantener, contener, retener, obtener, detener, sostener all use -tendr-. Componer, suponer, proponer, imponer, oponer, posponer, exponer, disponer all use -pondr-. Convenir, intervenir, prevenir all use -vendr-. The list of twelve actually unlocks several dozen verbs once you count compounds.

Group 2: the dropped-vowel verbs (poder, saber, caber, querer, haber)

These five verbs drop the -e- of the infinitive entirely. Note that querer keeps both r's, producing the distinctive double-rr of querré — easily confused in spelling with quiere (present indicative) or with the conditional querría.

Caber (to fit) is the rarest of the group in everyday speech, but it appears in fixed phrases — no cabe duda (there's no doubt) — and you should recognise cabrá / cabrán when you meet them.

Haber in the future has two distinct lives:

1. As the auxiliary of the future perfect: habré comido (I will have eaten), habrán llegado (they will have arrived).
2. As the impersonal of existence in the future: habrá problemas (there will be problems), habrá una reunión mañana (there will be a meeting tomorrow). Like hay in the present, this form never agrees in number — habrá problemas with one r, never habrán problemas.

The double -rr- in querer is genuine and obligatory: the original -r of the infinitive plus the -r- of the future stem. Querré with a single r is a spelling error.

Group 3: the contracted stems (hacer, decir)

Two verbs go further than the others: they don't just drop a vowel, they collapse the whole infinitive into a short stem.

These two are arbitrarily short — no other irregular future is this contracted. Compounds follow the same path: deshacer → desharé, rehacer → reharé, contradecir → contradiré, predecir → prediré. Note that bendecir and maldecir are exceptions among the compounds of decir: their modern futures are regular (bendeciré, maldeciré), not contracted — so predecir and contradecir are the cleaner analogs to the dir- pattern.

All twelve, at a glance

For revision, here is the full list in one block, with the yo form as the anchor:

The conditional bonus: same stems

Here is the most useful single fact about the irregular future stems: the conditional uses the exact same stems. The endings change (-ía, -ías, -ía, -íamos, -íais, -ían), but the stems are identical.

This is one of the most economical pieces of Spanish grammar: twelve stems, two tenses, no extra memorisation. If you can produce tendré, you can produce tendría by reflex.

The future perfect: built on habré

The future perfect uses the future of haber — habré, habrás, habrá, habremos, habréis, habrán — plus the past participle. It expresses an action that will be complete by a future reference point.

The future of haber is also used for conjecture about the recent past, parallel to the conjectural use of the simple future for present speculation: Habrán llegado ya — They must have arrived by now.

Stress and accents: identical to regular verbs

Because the endings are unchanged, the accent pattern for irregular-stem futures is identical to the regular pattern:

• Accents on -é, -ás, -á, -éis, -án (five of six forms).
• No accent on -emos (nosotros).
• The accent is always on the final syllable of the ending.

Are there other irregular futures? No.

These twelve are the complete list of irregular future stems in Spanish. There are no other surprises hidden in lower-frequency vocabulary. Verbs you might suspect are irregular — aprender, escribir, abrir, ver — all use their full infinitive as the stem in the future: aprenderé, escribiré, abriré, veré.

Compounds of the twelve follow the parent verb (so componer → compondré, mantener → mantendré, suponer → supondré, deshacer → desharé), but these are not new patterns — they are the same stems with a prefix.

Common Mistakes

Tener uses the stem tendr-, not the full infinitive. The same is true for the compounds mantener, contener, obtener, retener, detener, sostener.

Poner and its compounds (componer, suponer, proponer, imponer) use pondr-. The pattern is identical to tener: replace the vowel before -r with -d-.

Decir contracts heavily to dir- in the future. The same goes for predecir → prediré and contradecir → contradiré.

The impersonal future of haber is invariably habrá, even with a plural complement — exactly like hay in the present. Habrán is only correct when haber is the auxiliary of the future perfect (habrán llegado = they will have arrived).

Querer doubles its r in the future: querré, querrás, querrá, querremos, querréis, querrán. The first r belongs to the stem (quer-), the second to the future morpheme (-r-). Both are needed.

The peninsular vosotros ending -éis always carries the accent on the é, including with irregular-stem verbs. Saldreis without the accent is a spelling error.

Key Takeaways

• The simple future has twelve verbs with irregular stems — no more, no less.
• The endings (-é, -ás, -á, -emos, -éis, -án) and their accent pattern are identical to the regular future.
• The twelve fall into three groups: insert -d- (tendr-, pondr-, saldr-, vendr-, valdr-), drop the -e- (podr-, sabr-, cabr-, querr-, habr-), or contract heavily (har-, dir-).
• The same stems power the conditional — learning them once unlocks both tenses.
• Compounds (mantener, componer, predecir, etc.) follow the parent verb's irregular stem.
• Haber as an existential is always habrá (singular), even with plural complements; habrán is only the future-perfect auxiliary.
• Querer doubles its r in querré — the double -rr- is part of the spelling, not an error.